15 research outputs found
Isothermal titration calorimetry as a complementary method for investigating nanoparticle-protein interactions
Controlling protein interactions in blood for effective liver immunosuppressive therapy by silica nanocapsules
Immunosuppression with glucocorticoids is a common treatment for autoimmune liver diseases and after liver transplant, which is however associated with severe side-effects. Targeted delivery of glucocorticoids to inflammatory cells, e.g. liver macrophages and Kupffer cells, is a promising approach for minimizing side effects. Herein, we prepare coreâshell silica nanocapsules (SiO2 NCs) via a solâgel process confined in nanodroplets for targeted delivery of dexamethasone (DXM) for liver immunosuppressive therapy. DXM with concentrations up to 100 mg mLâ1 in olive oil are encapsulated while encapsulation efficiency remains over 95% after 15 days. Internalization of NCs by non-parenchymal murine liver cells significantly reduces the release of inflammatory cytokines, indicating an effective suppression of inflammatory response of liver macrophages. Fluorescent and magnetic labeling of the NCs allows for monitoring their intracellular trafficking and biodegradation. Controlled interaction with blood proteins and good colloidal stability in blood plasma are achieved via PEGylation of the NCs. Specific proteins responsible for stealth effect, such as apolipoprotein A-I, apolipoprotein A-IV, and clusterin, are present in large amounts on the PEGylated NCs. In vivo biodistribution investigations prove an efficient accumulation of NCs in the liver, underlining the suitability of the SiO2 NCs as a dexamethasone carrier for treating inflammatory liver diseases.Fil: Jiang, Shuai. Max-Planck-Institut fĂŒr Polymerforschung; AlemaniaFil: Prozeller, Domenik. Max-Planck-Institut fĂŒr Polymerforschung; AlemaniaFil: Pereira, Jorge. Max-Planck-Institut fĂŒr Polymerforschung; AlemaniaFil: Simon, Johanna. Max-Planck-Institut fĂŒr Polymerforschung; Alemania. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Han, Shen. Max-Planck-Institut fĂŒr Polymerforschung; AlemaniaFil: Wirsching, Sebastian. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Fichter, Michael. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Mottola, Milagro. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones BiolĂłgicas y TecnolĂłgicas. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas, FĂsicas y Naturales. Instituto de Investigaciones BiolĂłgicas y TecnolĂłgicas; Argentina. Max-Planck-Institut fĂŒr Polymerforschung; AlemaniaFil: Lieberwirth, Ingo. Max-Planck-Institut fĂŒr Polymerforschung; AlemaniaFil: Morsbach, Svenja. Max-Planck-Institut fĂŒr Polymerforschung; AlemaniaFil: MailĂ€nder, Volker. Max-Planck-Institut fĂŒr Polymerforschung; Alemania. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Gehring, Stephan. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Crespy, Daniel. Max-Planck-Institut fĂŒr Polymerforschung; Alemania. Vidyasirimedhi Institute of Science and Technology; TailandiaFil: Landfester, Katharina. Max-Planck-Institut fĂŒr Polymerforschung; Alemani
Prevention of Dominant IgG Adsorption on Nanocarriers in IgGâEnriched Blood Plasma by Clusterin Precoating
Abstract Nanocarriers for medical applications must work reliably within organisms, independent of the individual differences in the blood proteome. Variation in the blood proteome, such as immunoglobulin levels, is a result of environmental, nutrition, and constitution conditions. This variation, however, should not influence the behavior of nanocarriers in biological media. The composition of the protein corona is investigated to understand the influence varying immunoglobulin levels in the blood plasma have on the interactions with nanocarriers. Specifically, the composition of the nanocarriers' coronas is analyzed after incubation in plasma with normal or elevated immunoglobulin G (IgG) levels, and cellular uptake is monitored in cell lines containing different immunoglobulin receptors. Here, it is reported that upon doubling the IgG concentration in plasma, the IgG fraction in the protein corona increases by a factor of 40 independent of the nanocarrier material. This results in a significant increase in uptake in cells exhibiting IgG binding receptors. Furthermore, precoating nanocarriers with clusterin successfully prevents dominant IgGâadsorption and additionally reduces cellular internalization, after incubation with IgGâenriched plasma. Therefore, precoating nanocarriers may be utilized as a powerful method to reduce the influence of individual variations in blood composition on the protein corona
Reliable and Easy-To-Use Liquid Chromatography-Tandem Mass Spectrometry Method for Simultaneous Analysis of Fluconazole, Isavuconazole, Itraconazole, Hydroxy-Itraconazole, Posaconazole, and Voriconazole in Human Plasma and Serum
Background: A fast and easy-to-use liquid chromatographytandem mass spectrometry method for the determination and quantification of 6 triazoles [fluconazole (FLZ), isavuconazole (ISZ), itraconazole (ITZ), hydroxy-itraconazole (OH-ITZ), posaconazole (PSZ), and voriconazole (VRZ)] in human plasma and serum was developed and validated for therapeutic drug monitoring. Methods: Sample preparation was based on protein precipitation with acetonitrile and subsequent centrifugation. Isotope-labeled analogues for each analyte were used as internal standards. Chromatographic separation was achieved using a 50 u 2.1 mm, 1.9 mm polar Hypersil Gold C18 column and mobile phase consisting of 0.1% formic acid/acetonitrile (45%/55%, vol/vol) at a flow rate of 340 mu L/min. The triazoles were simultaneously detected using a triple-stage quadrupole mass spectrometer operated in selected reaction monitoring mode with positive heated electrospray ionization within a single runtime of t = 3.00 minutes. Results: Linearity of all azole concentration ranges was verified by the Mandel test and demonstrated for all azoles. All calibration curves were linear and fitted using least squares regression with a weighting factor of the reciprocal concentration. Limits of detection (mu g/L/L) were FLZ, 9.3; ISZ, 0.3; ITZ, 0.6; OH-ITZ, 8.6; PSZ, 3.4; and VRZ, 2.1. The lower limits of quantitation (mu g/L/liter) were FLZ, 28.3; ISZ, 1.0; ITZ, 1.7; OH-ITZ, 26.2; PSZ, 10.3; and VRZ, 6.3. Intraday and interday precisions ranged from 0.6% to 6.6% for all azoles. Intraday and interday accuracies (% bias) of all analytes were within 10.5%. In addition, we report on a 29-year-old white woman (94 kg body weight) with a history of acute myeloid leukemia who underwent stem cell transplantation. Because of diagnosis of aspergillus pneumonia, antifungal pharmacotherapy was initiated with different application modes and dosages of ISZ, and plasma concentrations were monitored over a time period of 6 months. Conclusions: A precise and highly sensitive liquid chromatographytandem mass spectrometry method was developed that enables quantification of triazoles in plasma and serum matrix across therapeutically relevant concentration ranges. It was successfully implemented in our therapeutic drug monitoring routine service and is suitable for routine monitoring of antifungal therapy and in severely ill patients